The biggest news out of the Giants’ farm system this week was who left the farm, with outfielder Mac Williamson earning a promotion to San Francisco after a scalding hot start with the Triple-A Sacramento River Cats. Although no longer technically a prospect since he has already exhausted his MLB rookie eligibility, Williamson could still carve out a long-term role with the Giants in left field.

If Williamson struggles, the Giants don’t necessarily have to go back to Hunter Pence in left field. Prospects Steven Duggar and Austin Slater are heating up in Sacramento and Chris Shaw still profiles as the Giants’ best long-term option as the everyday left fielder.

The Giants have already had to borrow liberally from the Sacramento roster, with top pitching prospects Andrew Suarez and Tyler Beede making their major league debuts earlier this month. If the Giants fall out of contention by July, they could begin a rebuilding process that would include a decent portion...